The APX Resilient ATM UNI Interface Module is a member of the APX Universal Interface Module Range. The Resilient APX ATM Modules enable high availability circuits to be connected with a backup to ensure network survivability.

The Resilient module uses Automatic Protection Switching, operating in 1+1 mode, whereby if a fault is detected on the main, or working link, the interface will automatically switch to use the backup, or protection link. Once a fault has been detected switching will occur and service will resume within 50mS. Line monitoring is not limited to Loss of Signal allowing operation in networks where media converters will continue to provide a light source even in the event of a link breakage.

The Resilient Module provides a dual ATM interface port, although only one may be active at any time. LEDs are provided to indicate that real traffic is passing across the ATM interface and also to indicate which is the currently active port. The Modules are "Hot Swappable" to ease maintenance with replacement modules recovering immediately without further configuration.

The ATM module performs physical layer and ATM layer functions including framing, alarm processing and cell delineation. Flexible clock options remove network synchronisation problems. Statistics are gathered at all layers and loop backs are available to aid diagnostic functions. OEM Alarm and Loopback functions are supported as per UNI 3.1

Management and configuration of the ATM Module is achieved via the simple menu driven user interface and may be monitored using SNMP Traps.

Optionally, the ATM module may be fitted with the Policing Module allowing individual PVC's to be monitored according to pre determined service levels and violating cells may be discarded or tagged as low priority.